Semiconductor devices such as memory devices reside in many computers and electronic products to store data. A typical semiconductor device has many layers of different materials formed on a semiconductor wafer.
During manufacturing, the layers go through many processes. For example, a patterning process puts patterns on the layers. Some patterning processes use a mask to transfer patterns from the mask to the layers underneath the mask.
Some conventional masks are made of amorphous carbon. However, an amorphous carbon mask at some thickness may have a high absorption of optical light, causing the amorphous carbon mask inapplicable for some processes.